A large class of theoretical models posits that voters choose candidates on the basis of issue congruence, but convincing empirical tests of this key claim remain elusive. The most persistent difficulty is obtaining comparable spatial estimates for winning and losing candidates, as well as...

A large class of theoretical models posits that voters choose candidates on the basis of issue congruence, but convincing empirical tests of this key claim remain elusive. The most persistent difficulty is obtaining comparable spatial estimates for winning and losing candidates, as well as...

Income inequality and political polarization have both increased dramatically in the United States over the last several decades. A small but growing literature has suggested that these two phenomena may be related and mutually reinforcing: income inequality leads to political polarization, and...

Why do state legislators vote the way they do? Which influence is predominant: ideology, party, or public opinion? The implementation votes surrounding the Affordable Care Act (ACA) provides a unique setting to examine this question, as they make all three considerations highly salient. State...

We introduce experimental research design to the study of policy diffusion in order to better understand the role of political ideology in policymakers’ willingness to learn from one another’s experiences. Our two experiments, embedded in national surveys of U.S. municipal officials, expose...

The Evolution of Cooperation, by Axelrod (1984), is a highly influential study that identifies the benefits of cooperative strategies in the iterated prisoner's dilemma. We argue that the most extensive historical analysis in the book, a study of cooperative behavior in First World War trenches,...